In-situ sensors enable researchers to investigate real-time chemical dynamics in the environment, thereby greatly improving sampling densities and providing the capability for autonomous measurements in harsh environments. For example, deployed sensors can be used to detect, quantify and trace harmful and toxic chemicals that have been released in populated areas. Miniaturized mass spectrometers (MS) can be especially versatile and powerful as sensors for on-site identification and characterization of a wide variety of chemicals. Miniaturization is desirable for field-deployed mass spectrometers because of the corresponding reduction of electrical power consumption, simplification of vacuum systems, and the possibility for rapid parallel chemical analysis.
Recent efforts in extreme miniaturization of mass spectrometers and their components have been stimulated by opportunities arising from micro-fabrication techniques and advances in materials sciences. Previous attempts have focused on micro-fabrication of as many as a million micron-sized cylindrical ion trap (CIT) mass spectrometer arrays on silicon wafers. While an array-based approach for MS miniaturization can be useful to compensate for the reduced signal intensities that result from miniaturization of each mass spectrometer, affordable batch fabrication of such arrays remains a challenge.